Keyless Coupling Arrangement for a Generator and Associated Methods

ABSTRACT

Described is a generator for an engine-driven power system. The generator having a generator shaft, a sleeve coupler, a first pulley, and a second pulley. The generator shaft, which is shaped at an end to define a first tapered surface, rotates a rotor relative to a stator. The sleeve coupler is shaped to define a bore with a second tapered surface. The bore receives the end of the generator shaft. The first pulley has a center hole to receive the sleeve coupler. The second pulley shares an axis of rotation with the first pulley and transfers a rotational force to the generator shaft and to the sleeve coupler.

FIELD

The present disclosure is directed to engine-driven power systems and,more particularly, to power systems with a generator having a keylesscoupling arrangement.

BACKGROUND

Conventionally, engine-driven power systems include an engine configuredto operate various driven components, such a generators, aircompressors, and the like. Sometimes it is desirable to adjust therotational speed from the engine to meet the rotational speed needs ofthe various driven components via a belt system. For example, agenerator and an air compressor may operate at different rotationalspeeds. While existing belt systems can adjust the rotational speed, itis desirable to adjust the rotational speed in engine-driven powersystems more economically and efficiently, while also reducingcomplexity and noise.

SUMMARY

Power systems configured to operate at a non-synchronous speed aredisclosed, substantially as illustrated by and described in connectionwith at least one of the figures.

According to a first aspect, a generator for an engine-driven powersystem comprises: a generator shaft configured to rotate a rotorrelative to a stator, wherein the generator shaft is shaped at an end todefine a first tapered surface; a sleeve coupler shaped to define a borewith a second tapered surface, wherein the bore is configured to receivethe end of the generator shaft; a first pulley having a center hole thatis configured to receive the sleeve coupler; and a second pulleyconfigured to transfer a rotational force to the generator shaft and tothe sleeve coupler, wherein the first pulley and the second pulley sharean axis of rotation.

In certain aspects, the first pulley comprises a clutch mechanism.

In certain aspects, the first tapered surface and the second taperedsurface are complimentary to one another.

In certain aspects, the sleeve coupler comprises an exterior surfacewith a third tapered surface.

In certain aspects, the center hole comprises a fourth tapered surfacethat is complimentary to the third tapered surface.

In certain aspects, the generator further comprises a bolt that securesthe first pulley, the second pulley, and the sleeve coupler to thegenerator shaft.

In certain aspects, the bolt passes through the first pulley, the secondpulley, and the sleeve coupler and into a threaded shaft hole of thegenerator shaft.

In certain aspects, the second pulley is coupled to the sleeve couplervia one or more drive pins configured to transfer torque from the secondpulley to the sleeve coupler.

In certain aspects, the second pulley engages the sleeve coupler via aprotruding flange.

In certain aspects, the sleeve coupler comprises a threaded couplerconfigured to receive a removal bolt.

In certain aspects, driving the removal bolt into the threaded couplerpushes an end of the removal bolt against an end of the generator shaftto bias the sleeve coupler away from the generator shaft.

According to a second aspect, a method of assembling a generator for anengine-driven power system comprises: sliding a sleeve coupler onto agenerator shaft, wherein the generator shaft is shaped at an end todefine a first tapered surface, and wherein the sleeve coupler is shapedto define a bore with a second tapered surface that is configured toreceive the end of the generator shaft; sliding a first pulley onto thesleeve coupler, wherein the first pulley defines a center hole that isconfigured to receive the sleeve coupler; sliding a second pulley ontothe sleeve coupler adjacent the first pulley, wherein the first pulleyand the second pulley share an axis of rotation; and passing a boltthrough the sleeve coupler, the first pulley, and the second pulley andinto a threaded shaft hole of the generator shaft to secure the sleevecoupler, the first pulley, and the second pulley relative to thegenerator shaft, wherein the second pulley is configured to transfer arotational force to the sleeve coupler, the first pulley, and thegenerator shaft.

In certain aspects, the second pulley comprises one or more drive pinsand the sleeve coupler comprises one or more holes arranged tocorrespond with the one or more drive pins.

In certain aspects, the method further comprises the step of passing theone or more drive pins into the one or more holes when sliding thesecond pulley onto the sleeve coupler.

In certain aspects, the first pulley comprises a clutch mechanism.

In certain aspects, the first tapered surface and the second taperedsurface are complimentary to one another.

In certain aspects, the sleeve coupler shaped to define an exteriorsurface with a third tapered surface.

In certain aspects, the center hole defines a fourth tapered surfacethat is complimentary to the third tapered surface.

In certain aspects, the second pulley engages the sleeve coupler via aprotruding flange.

According to a third aspect, a generator for an engine-driven powersystem comprises: a generator shaft configured to rotate a rotorrelative to a stator, wherein the generator shaft is shaped at an end todefine a first tapered surface; a sleeve coupler shaped to define a borewith a second tapered surface, wherein the bore is configured to receivethe end of the generator shaft, and wherein the sleeve coupler shaped todefine an exterior surface with a third tapered surface; a first pulleyhaving a center hole that is configured to receive the sleeve coupler,wherein the first pulley comprises a clutch mechanism, wherein thecenter hole defines a fourth tapered surface that is complimentary tothe third tapered surface; a second pulley configured to transfer arotational force to the generator shaft and to the sleeve coupler,wherein the first pulley and the second pulley share an axis of rotationand the second pulley is coupled to the sleeve coupler via one or moredrive pins.

In certain aspects, the second pulley is coupled to the generator shaftvia a bolt that secures the sleeve coupler relative to each of thegenerator shaft and the first pulley.

In certain aspects, the second pulley engages the sleeve coupler via aprotruding flange.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features, and advantages of thedevices, systems, and methods described herein will be apparent from thefollowing description of particular embodiments thereof, as illustratedin the accompanying figures; where like or similar reference numbersrefer to like or similar structures. The figures are not necessarily toscale, emphasis instead being placed upon illustrating the principles ofthe devices, systems, and methods described herein.

FIG. 1a illustrates a perspective view of an example power system havinga power unit arranged within an enclosure.

FIG. 1b illustrates a perspective view of the example power system withportions of the enclosure removed to better illustrate the power unit.

FIG. 1c illustrates a schematic diagram of the example power system.

FIGS. 2a and 2b illustrate perspective views of the drive system of theexample power system.

FIG. 2c illustrates a perspective cut-away view of the generator of theexample power system.

FIG. 3a illustrates a cross-sectional perspective side view of thegenerator of FIG. 2 c.

FIG. 3b illustrates a front perspective side view of the generator shaftand pulleys of the generator of FIG. 3 a.

FIG. 3c illustrates a front perspective assembly view of the generatorshaft and pulleys of the generator of FIG. 3 a.

FIG. 3d illustrates a rear perspective view of the driven generatorpulley of FIGS. 3b and 3 c.

FIG. 4 illustrates an example method of assembling and driving thegenerator in the example power system.

FIG. 5 illustrates an example method of disassembling the generator inthe example power system.

DETAILED DESCRIPTION

References to items in the singular should be understood to includeitems in the plural, and vice versa, unless explicitly stated otherwiseor clear from the text. Grammatical conjunctions are intended to expressany and all disjunctive and conjunctive combinations of conjoinedclauses, sentences, words, and the like, unless otherwise stated orclear from the context. Recitation of ranges of values herein are notintended to be limiting, referring instead individually to any and allvalues falling within the range, unless otherwise indicated herein, andeach separate value within such a range is incorporated into thespecification as if it were individually recited herein. In thefollowing description, it is understood that terms such as “first,”“second,” “top,” “bottom,” “side,” “front,” “back,” and the like arewords of convenience and are not to be construed as limiting terms. Forexample, while in some examples a first side is located adjacent or neara second side, the terms “first side” and “second side” do not imply anyspecific order in which the sides are ordered.

As used herein, the terms “about,” “approximately,” “substantially,” orthe like, when accompanying a numerical value, are to be construed asindicating a deviation as would be appreciated by one of ordinary skillin the art to operate satisfactorily for an intended purpose. Ranges ofvalues and/or numeric values are provided herein as examples only, anddo not constitute a limitation on the scope of the describedembodiments. The use of any and all examples, or exemplary language(“e.g.,” “such as,” or the like) provided herein, is intended merely tobetter illuminate the embodiments and does not pose a limitation on thescope of the embodiments. The terms “e.g.,” and “for example” set offlists of one or more non-limiting examples, instances, or illustrations.No language in the specification should be construed as indicating anyunclaimed element as essential to the practice of the embodiments.

As used herein, the term “and/or” means any one or more of the items inthe list joined by “and/or.” As an example, “x and/or y” means anyelement of the three-element set {(x), (y), (x, y)}. In other words, “xand/or y” means “one or both of x and y”. As another example, “x, y,and/or z” means any element of the seven-element set {(x), (y), (z), (x,y), (x, z), (y, z), (x, y, z)}. In other words, “x, y, and/or z” means“one or more of x, y, and z.”

As used herein, the terms “drivingly coupled,” “drivingly coupled to,”and “drivingly coupled with” as used herein, each mean a mechanicalconnection that enables a driving part, device, apparatus, or componentto transfer a mechanical force to a driven part, device, apparatus, orcomponent.

As used herein, circuitry or a device is “operable” to perform afunction whenever the circuitry or device comprises the necessaryhardware and code (if any is necessary) to perform the function,regardless of whether performance of the function is disabled, or notenabled (e.g., by a user-configurable setting, factory trim, etc.).

As used herein, “power conversion circuitry” refers to circuitry and/orelectrical components that convert electrical power from one or morefirst forms (e.g., power output by a generator) to one or more secondforms having any combination of voltage, current, frequency, and/orresponse characteristics. The power conversion circuitry may includesafety circuitry, output selection circuitry, measurement and/or controlcircuitry, and/or any other circuits to provide appropriate features.

As used herein, the term “processor” means processing devices,apparatuses, programs, circuits, components, systems, and subsystems,whether implemented in hardware, tangibly embodied software, or both,and whether or not it is programmable. The term “processor” as usedherein includes, but is not limited to, one or more computing devices,hardwired circuits, signal-modifying devices and systems, devices andmachines for controlling systems, central processing units, programmabledevices and systems, field-programmable gate arrays,application-specific integrated circuits, systems on a chip, systemscomprising discrete elements and/or circuits, state machines, virtualmachines, data processors, processing facilities, and combinations ofany of the foregoing. The processor may be, for example, any type ofgeneral purpose microprocessor or microcontroller, a digital signalprocessing (DSP) processor, an application-specific integrated circuit(ASIC). The processor may be coupled to, or integrated with a memorydevice. The memory device can be any suitable type of computer memory orany other type of electronic storage medium, such as, for example,read-only memory (ROM), random access memory (RAM), cache memory,compact disc read-only memory (CDROM), electro-optical memory,magneto-optical memory, programmable read-only memory (PROM), erasableprogrammable read-only memory (EPROM), electrically-erasableprogrammable read-only memory (EEPROM), a computer-readable medium, orthe like.

Power systems, such as engine-driven units and other equipment, aresometimes permanently mounted to a work truck body in one or moremounting locations. Example power systems that have enclosures includeengine-driven generators, welders, air compressors, and combinationsthereof (e.g., a multi-use engine driven power units, such as the EnPak®power system available from Miller Electric Mfg. LLC). The mountinglocations of a work truck body typically include, for example, the sideon top of the tool box, the load space behind the cab (e.g., in-betweenthe toolboxes), and/or under the deck of the body (e.g., in front of therear axle).

FIGS. 1a and 1b illustrate perspective views of an example power system100. Specifically, FIG. 1a illustrates the example power system 100 withits enclosure 104 assembled, while FIG. 1b illustrates the example powersystem 100 with selected panels of the enclosure 104 removed. Theexample power system 100 includes a power unit 102 arranged within anenclosure 104. The enclosure 104 is primarily constructed with sheetmetal, and may include multiple panels.

Service access to the power unit 102 can be provided by a removablepanel (e.g., by fasteners), a door (e.g., via a hinged panel), a void inthe enclosure, or by any other suitable method or design. Therefore, oneor more of the panels or portions of the enclosure 104 may be removableand/or otherwise open to permit service access to the power unit 102.For example, a primary removable access panel 106 may be secured to alateral side of the enclosure 104 via one or more latches 110 that canspan the entire length of the enclosure 104 to facilitate convenient,single-side service access to the components of the power unit 102located within interior of the enclosure 104. In some examples, theremovable access panel 106 may be hingedly coupled to the enclosure 104.

In addition to the removable access panel 106, one or more secondaryremovable access panels 108 may be secured to the enclosure 104 viausing mechanical fasteners 112, such as screws, bolts, clips, snaps,etc. In either case, as best illustrated in FIG. 1b , the primary andsecondary removable access panels 106, 108 may be provided at the topside, bottom side, first lateral side, second lateral side, rear side,and/or front side of the enclosure 104 to facilitate access to andmaintenance of the power unit 102 or portions thereof. Relative terms(e.g., front/rear, etc.) are used to aid in the reader's understandingof the enclosure's configuration. Although relative terms are used todescribe the various surfaces and sides of the enclosure 104, any sidecan be considered a top/bottom/front/rear/first side/second side,depending on a particular design of the power system 100, theinstallation configuration, and/or perspective of the viewer.

The arrangements of the power unit 102 can be more easily understoodfrom FIG. 1c , which illustrates the components of an engine-drivenpower system. As illustrated, the power system 100 includes an engine114 and a generator 118, where the engine 114 is configured to drive agenerator 118 to generate electrical power. Specifically, FIG. 1cillustrates a schematic diagram of the power system 100. As illustrated,the example power system 100 may comprise the engine 114, one or morefuel tanks 116, a generator 118, power conversion circuitry 120, an aircompressor 122 configured to output pneumatic power, a welding-typepower supply 148 configured to output welding-type power (e.g., aninverter-based welder), one or more power outlets 150, a battery charger152, one or more fan assemblies 134, a processor 154, a memory device162, one or more sensors 156, and/or a hydraulic pump 164 configured tooutput hydraulic power. The example hydraulic pump 164 and the aircompressor 122 may be powered by mechanical power from the engine 114and/or by electrical power from the generator 118. The example powersystem 100 may further or alternatively include other components notspecifically discussed herein.

The engine 114 receives fuel from one of the one or more fuel tanks 116via one or more fuel lines 138. The engine 114 may be a diesel orgasoline engine configured to output, for example, between 20 and 50horse power. In one example, the engine 114 may be a small inline dieselengine. The engine 114 is controllable to operate at multiple speeds,such as an idle (e.g., no or minimal load speed) and a maximum speed(e.g., the maximum rated power of the engine 114). The engine speed maybe increased and/or decreased based on the load. The engine 114 isoperatively coupled with a muffler 146, which may be configured tooutput exhaust from the engine 114 via an exhaust pipe 132.

The fuel tank 116 may be located within the enclosure 104 or external tothe enclosure 104. For example, the engine 114 may draw fuel from a fueltank 116 that is external to the enclosure 104 via fuel line 138, suchas a fuel tank 116 of the vehicle 158 (e.g., a work truck) to which thepower system 100 is mounted (e.g., via mount brackets 140). The engine114 is mechanically coupled or linked to a generator shaft of thegenerator 118. For example, the engine 114 is configured to output arotational force either directly or via a driveshaft 160.

The generator 118 generates output power based on the mechanical inputfrom the engine 114. Specifically, the generator 118 is configured togenerate electric power using the rotational force from the engine 114.The generator 118 supplies the electrical power to the power conversioncircuitry 120. In some examples, the generator 118 is implemented usinga high-output alternator. Collectively, the engine 114 and the generator118 provide mechanical power and/or electrical power to powersubsystems.

The power conversion circuitry 120 provides one or more types ofelectrical power suitable for specific and/or general purpose uses. Theexample power conversion circuitry 120 may include one or more powersubsystems, such as the welding-type power supply 148, an auxiliarypower supply configured to output AC power (e.g., 120 VAC, 240 VAC, 50Hz, 60 Hz, etc.) and/or DC power (e.g., 12 VDC, 24 VDC, battery chargingpower, etc.) to the power outlets 150, and/or a vehicle power subsystemconfigured to convert electrical power to at least one of AC power or DCpower to power or charge at least one component of a vehicle (e.g.,battery charger 152), such as the vehicle 158 on which the power system100 is mounted. The welding-type power supply 148 converts output powerfrom the generator 118 to welding-type power based on a commandedwelding-type output. The welding-type power supply 148 provides currentat a desired voltage (e.g., from a user interface) to an electrode and aworkpiece to perform a welding-type operation.

The power conversion circuitry 120 may include, for example, a switchedmode power supply or an inverter fed from an intermediate voltage bus.Power conditioning circuitry may include a direct connection from apower circuit to the output (such as to the weld studs), and/or anindirect connection through power processing circuitry such as filters,converters, transformers, rectifiers, etc. For example, the powerconversion circuitry 120 may convert, invert, or otherwise process powerfrom the generator 118 to output an operating power to the aircompressor 122 (e.g., where an electric air compressor is used), awelding power to the welding-type power supply 148, 110 VAC and/or 220VAC power to a power outlet 150, a battery charging power to a batterycharger 152 (e.g., via battery clamps), and/or any other type ofelectrical power. In other examples, such as the configurationillustrated in FIG. 2a , the air compressor 122 may be driven by theengine 114 via a drive system 202 having one more belts and/or pulleys.In this example, the air compressor 122 may be a rotary screw aircompressor. For example, the generator 118 may include a clutch fortransmission of rotational force from the engine 114 to the aircompressor 122 via the one more belts and/or pulleys.

While illustrated as separate blocks, the power conversion circuitry 120may be integrated, or otherwise share circuitry, with other components,such as the welding-type power supply 148. For example, the powerconversion circuitry 120 may be configured to provide a welding currentdirectly to a welding torch without requiring additional circuitry orpower processing.

The control circuitry 166 employs a processor 154 is operatively coupledwith a memory device 162 (e.g., read-only memory (ROM), random accessmemory (RAM), etc.) configured to monitor and/or control the variousfunctions and statuses of the power system 100. For example, one or moreoperations of the power system 100 may be controlled by the processor154 in accordance with instructions (e.g., software algorithms) storedto a memory device 162 and/or based on an operational status of the ofthe power system 100.

The one or more fan assemblies 134 are configured to urge cooling airthrough the enclosure 104 to cool one or more components of the powerunit 102. While the fan assembly 134 is the primary driver of the airthrough the enclosure, in some examples, other components of the powersystem 100 may employ dedicated fans. For example, the generator 118 mayinclude a small generator fan to specifically cool the generatorwindings. Like the fan assembly 134, the generator fan moves air to anair outlet location. The generator fan can be significantly smaller thanthe fan assembly 134 and is not the primary driver of the air flow,because the generator fan is sized to cool only the generator 118.

The one or more sensors 156 (e.g., temperature sensor, humidity sensor,voltage sensors, current sensors etc.) may be located throughout thepower unit 102 and configured to monitor one or more conditions of thepower unit 102 or environment surrounding the power unit 102.

The engine 114 in an engine-driven generator, such as the power system100, may be operated at one or more desired speeds. In the case of asmall diesel engine, the engine 114 may be operated at a speed between1,800 and 4,000 revolutions per minute (RPM), where a high speedoperation is generally about 3,600 RPM and a low speed operation isgenerally about 1,800 RPM. In one example, the engine 114 may beoperated at 3,600 RPM to achieve high power in a small and light productpackage. In one example, the generator 118 may be a 2-pole generatorconfigured to operate at 3,600 RPM (for full power). In this example,the generator 118 can be directly connected to the flywheel side of theengine 114 because the engine 114 and the generator 118 are synchronousrelative to one another (i.e., they each operate at the same speed, forexample, 3,600 RPM). A high speed operation (e.g., 3,600 RPM), however,results in increased noise and vibration compared a low speed operation.Driving the generator 118 configured for 3,600 RPM at a low speedoperation (e.g., 1,800 RPM) may not provide adequate power. In order toproduce a power system 100 where a lower speed engine 114 can be used,the drive system 202 may be configured to convert the lowernon-synchronous speed from the engine 114 to a higher speed needed forthe generator 118 (e.g., 3,600 RPM) and/or other belt-driven components(e.g., greater than 4,000 RPM).

FIGS. 2a and 2b illustrate perspective views of the example power system100 with components removed to better illustrate the driveshaft 160, thedrive system 202, the generator 118, and the air compressor 122. Theengine 114 (illustrated in broken lines) is drivingly coupled to thedrive system 202. In one example, the engine 114 is configured to outputa rotational force to the drive system 202 via the driveshaft 160. Thedriveshaft 160 may be coupled to the engine 114 via a coupler 216. Thedrive system 202 involves a set of multiple pulleys that are drivinglycoupled to one another via one or more belts 204 at a fixed pulleyratio.

When a single belt 204 is used to drive all of the components, thespeeds of the components should be relatively similar to avoid verylarge or very small pulley diameters. A problem with this approach isthat some belt-driven components, such as the air compressor 122, have ahigh operating speed compared to common driven components. For example,the air compressor 122 may be a rotary screw type air compressor thatprovides continuous air output while maintain a small and quiet package.Rotary screw air compressors, however, operate at relatively high speeds(e.g., 4,000 to 10,000 RPM), whereas engines used to operate these aircompressors 122 in mobile power system 100 operate at much lower speeds(e.g., 1,800 to 4,000 RPM, often around 3,600 RPM). Therefore, a largespeed ratio is needed between the engine 114 and air compressor 122.

This speed ratio is often too large to achieve using a single belt,which is further complicated when a pulley comprises an integratedclutch. For example, the clutch would either have to be very large orvery small on the belt pulley diameter, which is difficult to achieveefficiently. Other approaches to managing the large speed ratio includeproviding an undersized belt-driven pulley 202 c at the air compressor122 to drive the air compressor 122, adding gears to the compressorassembly, and/or adding a jackshaft with two differently sized,concentric pulleys.

The jackshaft can include a clutch that is placed on the jackshaft asthe larger of the two pulleys on the shaft. In operation, the jackshaftspins at an intermediate speed to provide a step-up in speed (e.g., asan intermediate). For example, the engine 114 may be operating at 3,600RPM with a belt ratio (e.g., via the drive system 202) to get thejackshaft to 6,000 RPM and from the jackshaft to the compressor at10,000 RPM (via the two different pulleys of the jackshaft). When aclutch is used on the jackshaft, the clutch typically has a straightbore and the smaller drive pulley also a straight bore, both with keysand set crews for attachment. Other approaches use a split taper bushingfor the clutch and a second split taper bushing for the smaller drivepulley, again with a keyed shaft. One complication with theseapproaches, in addition to increasing the cost and the number ofcomponents, is that a keyed shaft is used, which can be difficult toalign with other pulleys/components. A keyed shaft design can also bedifficult to assemble and/or disassemble in the field when a repair isneeded. For example, the power system 100 may need to be serviced toreplace one or more parts in the field, which would warrant easyassembly and/or disassembly.

To address these complications, the generator 114 may include agenerator shaft 210 that supports a driven generator pulley 202 b and adriving generator pulley 202 d. In this arrangement, the generator shaft210 functions as an intermediate speed component of a drive system 202.The drive system 202 allows the engine 114 to drive the generator 118and other belt-driven components at full power and at a non-synchronousspeed, while also reducing noise and dampening vibration.

By setting the pulley ratio(s) of the drive system 202, the engine 114can operate at a first rotational speed and drive the generator 118 at asecond rotational speed and the air compressor 122 at a third rotationalspeed. The third rotational speed may be greater than the secondrotational speed, which, in turn, is greater than the first rotationalspeed. For example, the first rotational speed may be between 1,800revolutions per minute (RPM) and 3,200 RPM, the second rotational speedmay be between 3,200 RPM and 4,000 RPM, and the third rotational speedmay be between 4,000 RPM and 10,000 RPM.

The drive system 202 may comprise a drive pulley 202 a, a drivengenerator pulley 202 b, a belt-driven pulley 202 c, a driving generatorpulley 202 d, one or more idler pulleys 202 e, and/or one or moretensioners 208 drivingly coupled to one other via one or more belts 204.The driven generator pulley 202 b and the driving generator pulley 202 dmay have two different pulley sizes (e.g., pulley diameters) to reducesize, cost, and complexity by obviating the need for an undersizedbelt-driven pulley 202 c, additional gears, and/or the jackshaft. Thedriving generator pulley 202 d may further comprise an integratedclutch. Integrating the driven generator pulley 202 b, the drivinggenerator pulley 202 d, and/or clutch with the generator 118 reduces thenumber of drive components and thus creates a smaller drive systempackage for the power system 100. This arrangement has improvedstrength, assembly, disassembly, and alignment when compared to otherdesigns.

In some examples, a tensioner 208 is included to providing flexibilityfor the drive belt 204. Two or more the pulleys of the drive system 202may be fixed relative to each other via a bracket 206. Fixing two ormore pulleys relative to each other reduces relative motion and reducesdrive belt 204 wear and/or derailment (e.g., jumping off a pulley). Forexample, as illustrated, the bracket 206 provides a structure for thedrive pulley 202 a, the idler pulley 202 e, and tensioner 208. The drivebelt 204 may be fabricated from a vibration-dampening materials todampen transfer of vibrations (and noise) through the drive system 202and/or between the drive system 202, the generator 118, and the aircompressor 122.

As illustrated, the drive pulley 202 a and the driven generator pulley202 b are drivingly coupled to one another via one or more belts 204and/or one or more intermediate pulleys (e.g., idler pulley 202 e). Forexample, the power system 100 may also include an idler pulley 202 e anda tensioner 208, wherein the drive belt 204 links the generator clutch(e.g., via driven generator pulley 202 b), the belt-driven pulley 202 c(e.g., air compressor pulley), the idler pulley 202 e, and the tensioner208. In some examples, the engine 114 is configured to drive the drivebelt 204, such that the idler pulley 202 e and the tensioner 208 aredriven in a first rotational direction and the driven generator pulley202 b is driven in a second rotational direction opposite the firstrotational direction. In examples, the drive belt 204 is driven in atortuous path around the generator clutch, the belt-driven pulley 202 cof the air compressor 122, the idler pulley 202 e, and the tensioner208.

The fixed pulley ratio may be achieved by using pulleys of differentdiameter sizes to step up (or down, if desired) the rotational speed,RPM. For example, to step up the rotational speed, a drive pulley 202 amay be selected that has a diameter that is greater than the diameter ofthe driven generator pulley 202 b to achieve a desired fixed pulleyratio. The driveshaft 160 may be coupled to the drive pulley 202 a andconfigured to drive the drive pulley 202 a at the first rotationalspeed.

In one example, the power system 100 comprises an engine 114, agenerator 118, a belt-driven component, and a drive system 202. Thebelt-driven component may be, for example, an air compressor 122configured to output pneumatic power, a hydraulic pump 164 configured tooutput hydraulic power, or another belt-driven accessory. The drivesystem 202 comprises a drive pulley 202 a, a driven generator pulley 202b, a belt-driven pulley 202 c, and a driving generator pulley 202 d. Thepower system 100 typically has an engine 114 that drives the generator118, which is configured to convert mechanical power to electric powerto power, inter alia, the power conversion circuitry 120, thewelding-type power supply 148, etc.

FIG. 2c illustrates a cut away view of a generator 118 comprising agenerator shaft 210, a stator 118 a, and a rotor 118 b. The variousinternal windings of the stator 118 a and the rotor 118 b are omittedfrom the figure for clarity. The generator 118 is configured to convertmechanical power received at the generator shaft 210 to electric powerby rotating the rotor 118 b relative to the stator 118 a about an axisof rotation 212. The generator 118 is coupled to the driven generatorpulley 202 b and configured to receive the rotational force 214 via thegenerator shaft 210. The driven generator pulley 202 b may be coupled tothe generator 118 and configured to drive the generator 118.

In one example, the engine 114 is configured to output a rotationalforce 214 at a first rotational speed to rotate the drive pulley 202 a.The driven generator pulley 202 b is drivingly coupled to the drivepulley 202 a via a first belt 204. The driven generator pulley 202 b isconfigured to rotate the generator shaft 210 at a second rotationalspeed based on the first rotational speed. The second rotational speedis greater than the first rotational speed. For example, the firstrotational speed may be between 1,800 revolutions per minute (RPM) and3,200 RPM, while the second rotational speed may be between 3,200 RPMand 4,000 RPM.

The driving generator pulley 202 d is coupled to the generator shaft210. The driving generator pulley 202 d comprises an integrated clutchmechanism. The driving generator pulley 202 d has a first diameter thatis greater than a second diameter of the driven generator pulley 202 b.The driving generator pulley 202 d is configured to drive thebelt-driven pulley 202 c at a third rotational speed via a second belt204 based on rotation of the generator shaft 210 by the driven generatorpulley 202 b. The belt-driven pulley 202 c is configured to drive thebelt-driven component. The third rotational speed may be between 4,000RPM and 10,000 RPM. In one example, the third rotational speed may beabout 9,000 RPM The driven generator pulley 202 b and the drivinggenerator pulley 202 d share an axis of rotation 212. For example, thedriven generator pulley 202 b and the driving generator pulley 202 d maybe concentric. The belt-driven pulley 202 c may have a third diameterthat is less than the first diameter of the driving generator pulley 202d. Driving the air compressor 122 at a higher speed (e.g., the thirdrotational speed) allows for the compressor to be smaller and lowercost.

In some power systems, the air compressor 122 may be located next toand/or below the engine 114 to enable connection between the compressorshaft of the air compressor 122 and the engine shaft of the engine 114via a drive belt 204. In the illustrated power system 100, the aircompressor 122 is positioned above the generator 118, which reduces thedifficulty of servicing the air compressor 122, relative to conventionalpower systems, because the higher location in the enclosure positionsthe service points closer to top cover openings and/or side dooropenings that are generally easier to access for maintenance personnel.

As noted above, a keyed shaft can introduce certain complications whencoupling the driven generator pulley 202 b and the driving generatorpulley 202 d to the generator shaft 210. Therefore, rather than a keyedshaft, the driven generator pulley 202 b and the driving generatorpulley 202 d can be attached to the generator shaft 210 using a keylessshaft as illustrated in FIGS. 3a through 3d , for example. FIG. 3aillustrates a cross-sectional side view of the generator of FIG. 2c ,while FIGS. 3b and 3c illustrate, respectively, a front perspective sideview and a front perspective assembly view of the generator shaft 210and pulleys 202 b, 202 d. FIG. 3d illustrates a rear perspective view ofthe driven generator pulley 202 b. The disclosed arrangement offers alower cost, compact, lighter, more robust system. For example, thedisclosed power system 100 is easier to assemble and disassemble in thefactory and/or field, more resilient to bending stresses (e.g.,eliminating keyed shafts avoids stress concentrations and allows formore shaft diameter to pass through the assembly), and requires fewercomponents and machining.

As illustrated, the generator 118 comprises a generator shaft 210, arotor 118 b, and a stator 118 a. The generator shaft 210, which isconfigured to rotate the rotor 118 b relative to the stator 118 a, isshaped at a shaft end 210 a to define a first tapered surface 304 a. Thesleeve coupler 302 is shaped to define a bore 306, which may comprise asecond tapered surface 304 b. As illustrated, the bore 306 is configuredto receive the shaft end 210 a of the generator shaft 210. In otherwords, the first tapered surface 304 a is a keyless, shallow taper thatmates to the sleeve coupler 302 via a complimentary keyless, shallowtaper of the second tapered surface 304 b on the inside surface of thebore 306.

The sleeve coupler 302 is shaped to define an exterior surface with athird tapered surface 304 c. The driving generator pulley 202 d has acenter hole 308 that is configured to receive the sleeve coupler 302.The center hole 308 defines a fourth tapered surface 304 d. In otherwords, the third tapered surface 304 c is a keyless, shallow taper thatmates to the sleeve coupler 302 via a complimentary keyless, shallowtaper of the fourth tapered surface 304 d on the outside surface of thesleeve coupler 302.

The first tapered surface 304 a and the second tapered surface 304 b arecomplimentary to one another, while the third tapered surface 304 c andthe fourth tapered surface 304 d are complimentary to one another toincrease surface contact and, together with the bolt 314 when assembled,friction therebetween. The first tapered surface 304 a and the secondtapered surface 304 b contact one another to define a first taperedcontact region, while third tapered surface 304 c and the fourth taperedsurface 304 d contact one another to define a second tapered contactregion.

The driven generator pulley 202 b and the driving generator pulley 202 dshare an axis of rotation 212. The driven generator pulley 202 b, whichcomprises a center hole 310, is configured to transfer a rotationalforce 214 to the generator shaft 210 and to the sleeve coupler 302. Thedriving generator pulley 202 d may comprise an integrated clutchmechanism. For example, an electronic or mechanical clutch mechanism maybe integrated with the driving generator pulley 202 d.

In one example, the driven generator pulley 202 b is coupled to thesleeve coupler 302 via one or more drive pins 312. For example, thedriven generator pulley 202 b may comprise one or more drive pins 312and the sleeve coupler 302 may comprise one or more holes 318 arrangedto correspond with the one or more drive pins 312. The one or more drivepins 312 are configured to transfer torque from the driven generatorpulley 202 b to the sleeve coupler 302 via the one or more holes 318.The one or more drive pins 312 may be fixed to the driven generatorpulley 202 b or slipped within holes of the driven generator pulley 202b. In operation, the sleeve coupler 302 is driven by the drive pins 312that mate with the driven generator pulley 202 b such that the torque ofthe driven generator pulley 202 b is transferred through the drive pins312 to the sleeve coupler 302, which, in turn, is transferred to thedriving generator pulley 202 d and/or the generator shaft 210 at thefirst, second, third, and fourth tapered surfaces 304 a, 304 b, 304 c,304 d, both of which are driven by the driven generator pulley 202 b.

As best illustrated in FIG. 3d , the driven generator pulley 202 bengages the sleeve coupler 302 via a protruding flange 322 thatprotrudes from the driven generator pulley 202 b. The protruding flange322 can be configured to maintain the driven generator pulley 202 bconcentrically relative to the sleeve coupler 302 and/or to transfer aclamp load of the bolt 314 to the sleeve coupler 302 and drive pulley202 b. The inner diameter of the protruding flange 322 and the outerdiameter of the sleeve coupler 302 operates to position the drivinggenerator pulley 202 d concentric on the shaft.

A bolt 314, or other mechanical fastener, is used to secure the drivepulley 202 a, the driven generator pulley 202 b, and the sleeve coupler302 to the generator shaft 210. As illustrated in FIG. 3c , the bolt 314passes through the driven generator pulley 202 b (via center hole 310),the driving generator pulley 202 d (via center hole 308), and the sleevecoupler 302 (via bore 306) and into a threaded shaft hole 316 of thegenerator shaft 210. The inner diameter of the bore 306 at its narrowestpoint may be greater than the outer diameter of the shaft of the bolt314 at its widest point to prevent physical contact between the bolt 314and the sleeve coupler 302.

The protruding flange 322 of the driven generator pulley 202 b also actsto push on the driving generator pulley 202 d when the bolt 314 is drawntight. The axial force of the bolt 314 pulls on the generator shaft 210and pushes on the driving generator pulley 202 d. The bolt 314 clearsthe driving generator pulley 202 d and the sleeve coupler 302 such thatthe sleeve coupler 302 is free to float between the taper of the fourthtapered surface 304 d of the driving generator pulley 202 d and thefirst tapered surface 304 a of the generator shaft 210 duringinstallation. This floating effect allows a single bolt 314 to tightenboth first and second tapered contact regions at the same time andallows both tapered contact regions to be subject to the same axialforce (e.g., there is no bias to one taper over the other).

The sleeve coupler 302 may further comprise a threaded coupler 324configured to receive a removal bolt 320. The threaded coupler 324 maybe provided as threads on the inner surface of the bore 306 (e.g., atthe outer edge). Driving the removal bolt 320 into the threaded coupler324 pushes a bolt end 320 a of the removal bolt 320 against a shaft end210 a of the generator shaft 210 (e.g., at or near the threaded shafthole 316) to bias the sleeve coupler 302 and the driving generatorpulley 202 d away from the generator shaft 210. The removal bolt 320 mayhave a diameter that is greater than the bolt 314. The removal bolt 320obviates the need for a pulley puller tool, which would traditionally berequired.

As noted above, the power system 100 may need to be serviced to replaceone or more parts in the field. The disclosed power system 100 allowsfor the drive system 202 and/or the generator 118 to be more easilyassembled and disassembled.

FIG. 4 illustrates an example method 400 of assembling and driving agenerator 118 for an example power system 100.

At block 402, a sleeve coupler 302 is slid onto a generator shaft 210.The generator shaft 210 is shaped at a shaft end 210 a to define a firsttapered surface 304 a, while the sleeve coupler 302 is shaped to definea bore 306 with a second tapered surface 304 b that is configured toreceive the shaft end 210 a of the generator shaft 210.

At block 404, a driving generator pulley 202 d onto the sleeve coupler302, wherein the driving generator pulley 202 d defines a center hole308 that is configured to receive the sleeve coupler 302.

At block 406, a driven generator pulley 202 b is slide onto the sleevecoupler 302 adjacent the driving generator pulley 202 d. The drivengenerator pulley 202 b and the driving generator pulley 202 d share anaxis of rotation 212.

At block 408, a bolt 314 is passed through the sleeve coupler 302, thedriven generator pulley 202 b, and the driving generator pulley 202 dand into a threaded shaft hole 316 of the generator shaft 210. The bolt314 secures the sleeve coupler 302, the driven generator pulley 202 b,and the driving generator pulley 202 d relative to the generator shaft210.

At block 410, the bolt 314 may be tightened or torqued to fix the bolt314 relative to the generator shaft 210.

At block 412, where the driven generator pulley 202 b comprises one ormore drive pins 312 and the sleeve coupler 302 comprises one or moreholes 318 arranged to correspond with the one or more drive pins 312,the one or more drive pins 312 may be passed into the one or more holes318 when sliding the driven generator pulley 202 b onto the sleevecoupler 302.

At block 414, the driven generator pulley 202 b may be driven (e.g., viadrive pulley 202 a) to transfer a rotational force 214 to the sleevecoupler 302, the driving generator pulley 202 d, and the generator shaft210.

To disassemble the power system 100, the steps of FIG. 4 may be reversedas illustrated in FIG. 5, which illustrates an example method 500 ofdisassembling the generator 118 for an example power system 100.

At block 502, a bolt 314 is loosened relative to the generator shaft210.

At block 504, the bolt 314 is removed from the sleeve coupler 302, thedriven generator pulley 202 b, and the driving generator pulley 202 dand out of a threaded shaft hole 316 of the generator shaft 210.

At block 506, the driven generator pulley 202 b is slid off of thesleeve coupler 302.

At block 508, a removal bolt 320 may optionally be driven into athreaded coupler 324 of the sleeve coupler 302. Driving the removal bolt320 into the threaded coupler 324 pushes a bolt end 320 a of the removalbolt 320 against the shaft end 210 a of the generator shaft 210 to biasthe sleeve coupler 302 and the driving generator pulley 202 d away fromthe generator shaft 210. The removal bolt 320 is useful where the sleevecoupler 302 and/or driving generator pulley 202 d is stuck on thegenerator shaft 210 and obviates the need for a pulley puller.

At block 510, the sleeve coupler 302 with driving generator pulley 202 dis slid off of the generator shaft 210.

At block 512, the sleeve coupler 302 is removed (e.g., pressed, pushed,slid, or otherwise moved out) from the driving generator pulley 202 d.

While the present method and/or system has been described with referenceto certain implementations, it will be understood by those skilled inthe art that various changes may be made and equivalents may besubstituted without departing from the scope of the present methodand/or system. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the presentdisclosure without departing from its scope. For example, block and/orcomponents of disclosed examples may be combined, divided, re-arranged,and/or otherwise modified. Therefore, the present method and/or systemare not limited to the particular implementations disclosed. Instead,the present method and/or system will include all implementationsfalling within the scope of the appended claims, both literally andunder the doctrine of equivalents.

What is claimed is:
 1. A generator for an engine-driven power system,the generator comprising: a generator shaft configured to rotate a rotorrelative to a stator, wherein the generator shaft is shaped at an end todefine a first tapered surface; a sleeve coupler shaped to define a borewith a second tapered surface, wherein the bore is configured to receivethe end of the generator shaft; a first pulley having a center hole thatis configured to receive the sleeve coupler; and a second pulleyconfigured to transfer a rotational force to the generator shaft and tothe sleeve coupler, wherein the first pulley and the second pulley sharean axis of rotation.
 2. The generator of claim 1, wherein the firstpulley comprises a clutch mechanism.
 3. The generator of claim 1,wherein the first tapered surface and the second tapered surface arecomplimentary to one another.
 4. The generator of claim 1, wherein thesleeve coupler comprises an exterior surface with a third taperedsurface.
 5. The generator of claim 4, wherein the center hole comprisesa fourth tapered surface that is complimentary to the third taperedsurface.
 6. The generator of claim 1, further comprising a bolt thatsecures the first pulley, the second pulley, and the sleeve coupler tothe generator shaft.
 7. The generator of claim 6, wherein the boltpasses through the first pulley, the second pulley, and the sleevecoupler and into a threaded shaft hole of the generator shaft.
 8. Thegenerator of claim 1, wherein the second pulley is coupled to the sleevecoupler via one or more drive pins configured to transfer torque fromthe second pulley to the sleeve coupler.
 9. The generator of claim 1,wherein the second pulley engages the sleeve coupler via a protrudingflange.
 10. The generator of claim 1, wherein the sleeve couplercomprises a threaded coupler configured to receive a removal bolt. 11.The generator of claim 10, wherein driving the removal bolt into thethreaded coupler pushes an end of the removal bolt against an end of thegenerator shaft to bias the sleeve coupler away from the generatorshaft.
 12. A method of assembling a generator for an engine-driven powersystem, the method comprising: sliding a sleeve coupler onto a generatorshaft, wherein the generator shaft is shaped at an end to define a firsttapered surface, and wherein the sleeve coupler is shaped to define abore with a second tapered surface that is configured to receive the endof the generator shaft; sliding a first pulley onto the sleeve coupler,wherein the first pulley defines a center hole that is configured toreceive the sleeve coupler; sliding a second pulley onto the sleevecoupler adjacent the first pulley, wherein the first pulley and thesecond pulley share an axis of rotation; and passing a bolt through thesleeve coupler, the first pulley, and the second pulley and into athreaded shaft hole of the generator shaft to secure the sleeve coupler,the first pulley, and the second pulley relative to the generator shaft,wherein the second pulley is configured to transfer a rotational forceto the sleeve coupler, the first pulley, and the generator shaft. 13.The method of claim 12, wherein the second pulley comprises one or moredrive pins and the sleeve coupler comprises one or more holes arrangedto correspond with the one or more drive pins.
 14. The method of claim13, further comprising the step of passing the one or more drive pinsinto the one or more holes when sliding the second pulley onto thesleeve coupler.
 15. The method of claim 12, wherein the first pulleycomprises a clutch mechanism.
 16. The method of claim 12, wherein thefirst tapered surface and the second tapered surface are complimentaryto one another.
 17. The method of claim 12, wherein the sleeve couplershaped to define an exterior surface with a third tapered surface. 18.The method of claim 17, wherein the center hole defines a fourth taperedsurface that is complimentary to the third tapered surface.
 19. Themethod of claim 12, wherein the second pulley engages the sleeve couplervia a protruding flange.
 20. A generator for an engine-driven powersystem, the generator comprising: a generator shaft configured to rotatea rotor relative to a stator, wherein the generator shaft is shaped atan end to define a first tapered surface; a sleeve coupler shaped todefine a bore with a second tapered surface, wherein the bore isconfigured to receive the end of the generator shaft, and wherein thesleeve coupler shaped to define an exterior surface with a third taperedsurface; a first pulley having a center hole that is configured toreceive the sleeve coupler, wherein the first pulley comprises a clutchmechanism, wherein the center hole defines a fourth tapered surface thatis complimentary to the third tapered surface; a second pulleyconfigured to transfer a rotational force to the generator shaft and tothe sleeve coupler, wherein the first pulley and the second pulley sharean axis of rotation and the second pulley is coupled to the sleevecoupler via one or more drive pins.
 21. The generator of claim 20,wherein the second pulley is coupled to the generator shaft via a boltthat secures the sleeve coupler relative to each of the generator shaftand the first pulley.
 22. The generator of claim 20, wherein the secondpulley engages the sleeve coupler via a protruding flange.